Influencing factors of cardiac autonomic dysfunction in hemodialysis patients / 中华肾脏病杂志

Objective:To investigate the influencing factors of cardiac autonomic dysfunction in maintenance hemodialysis (MHD) patients by recording 48 h heart rate variability.Methods:It was a single-center cross-sectional study. MHD patients at the Hemodialysis Center of Peking University People's Hospital between October 1, 2021 and December 31, 2022 were enrolled in the study. These patients initiated hemodialysis for more than three months and were older than 18 years old, and patients with tachyarrhythmia, implanted cardiac pacemaker and the recording time less than 48 h were excluded. Demographic data, comorbidity, laboratory data, hemodialysis session data and heart rate variability were collected. Multivariate linear regression model was used to analyze the influencing factors for cardiac autonomic dysfunction in MHD patients.Results:A total of 110 patients were enrolled in the study, including 37 females (33.6%) and 36 diabetic patients (32.7%). The age of the patients was (57.8±14.8) years old, and the median dialysis vintage was 73.00(27.75±130.25) months. At baseline, the serum phosphate level was (1.6±0.4) mmol/L, and the N-terminal pro B-type natriuretic peptide (NT-proBNP) after ln transformed {ln[NT-proBNP(ng/L)]} was 8.4±1.2. The standard deviation of all normal R-R interval (SDNN) was (90.6±27.9) ms, ln[root mean square of successive differences in R-R interval (RMSSD, ms)] 3.2±0.8, ln[low frequency (ms 2)] 3.4±1.3, ln[high frequency (ms 2)] 3.1±1.4, and ln[low frequency/high frequency ratio] 0.28±0.64. After adjusting the age, coronary heart disease, diabetes, hemoglobin, serum phosphate and 25-hydroxy-vitamin D, serum natrium ( β=2.042, 95% CI 0.021–4.064, P=0.048) and ln[NT-proBNP (ng/L)] ( β=-7.027, 95% CI -12.247–-1.808, P=0.009) were independently correlated with SDNN (adjusted R2=0.218). Univariate linear regression model showed that diabetes was correlated with ln[low frequency(ms 2)] of MHD patients ( β=-0.659, 95% CI -1.171–-0.146, P=0.012), but in the multivariate linear regression model, significant correlation between diabetes and low frequency was not found. After adjusting the diabetes, coronary heart disease, dialysis vintage, hemoglobin, serum phosphate, serum albumin, pre-dialysis systolic blood pressure, post-dialysis systolic blood pressure, pre-dialysis diastolic blood pressure, increasing age ( β=-0.011, 95% CI -0.019–-0.003, P=0.007) and ln[NT-proBNP(ng/L)] ( β=-0.151, 95% CI -0.253–-0.048, P=0.004) were independently correlated with a decrease in the ln[low frequency/high frequency ratio]. In the multivariate linear regression model with ln[high frequency(ms 2)] or ln[RMSSD(ms)] as dependent variable, after adjusting the relevant factors, serum phosphate level was independently correlated with ln[RMSSD(ms)] ( β=-0.421, 95% CI -0.777–-0.065, P=0.021) or ln[high frequency(ms 2)] ( β=-0.752, 95% CI -1.325–-0.180, P=0.010). Conclusions:Hyperphosphatemia is an independent influencing factor of parasympathetic nervous system in MHD patients. Higher NT-proBNP is associated with lower SDNN and lower ratio of low frequency/high frequency, so serum phosphate control and volume control should be highlighted. Age is associated with autonomic dysfunction in MHD patients, so more attention should be paid to elder patients.

Micro-elimination of hepatitis C virus infection in the hemodialysis population / 临床肝胆病杂志

The hemodialysis population is increasing year by year in China. Due to the specific nature of hemodialysis treatment， the prevalence and incidence rates of hepatitis C virus （HCV） infection in hemodialysis patients are much higher than the general population. In order to achieve the WHO’s initiative to eliminate HCV by 2030 and realize the micro-elimination of HCV in the hemodialysis population， standard infection control and hand hygiene procedures should be implemented to cut off the route of iatrogenic infection， especially to prevent the outbreak of HCV infection in hemodialysis centers. Screening for HCV infection should be conducted for patients newly admitted to the hemodialysis center or transferred to another hemodialysis center， and regular screening should be conducted for patients receiving maintenance hemodialysis to identify new HCV infections in the early stage. It is also necessary to collaborate with specialists and provide direct-acting antiviral therapy for hemodialysis patients with HCV infection.

Interrelations among vascular calcification, bone density, osteoprotegerin and soluble receptor activator of nuclear factor kB ligand in hemodialysis patients / 中华肾脏病杂志

Objective To examine the interrelations among vascular calcification, bone denaity,osteoprotegerin (OPG) and soluble receptor activator of NF-kB ligand (sRANKL) in maintenance hemodialysis (MHD) patients. Methods The levels of serum OPG and sRANKL from 39 MHD patients were measured by ELISA. The vascular calcification was detected by plain radiographs. Bone mineral density (BMD) was measured with dual-energy X-ray absorptionmeter.Interrelations among above parameters were examined statistically. Results (1) Among 39 MHD patients, 25 cases were identified as vascular calcification by radiographic film. The proportion of patients with mild vascular calcification was 41.0% (16 cases), moderate and severe vascular calcification was 23.1% (9 cases). Compared to patients with mild vascular calcification,serum OPG level [(342.50±171.53) ng/L vs (206.21±137.88) ng/L,t=-2.253, P=0.0251 and OPG/sRANKL ratio (454.65±455.63 vs 135.31±136.81, t=59, P=0.035)were significantly higher in patients with moderate and severe vascular calcification,while serum sRANKL level [(0.10±0.08) pmol/L vs (0.12±0.08) pmol/L, t=0.534, P>0.05] was not significantly different. Multiple linear regression analysis showed that OPG/sRANKL ratio was independent factor of vascular calcification score. (2)Compared to patients with normal bone volume, the patients with abnormal bone volume had higher serum OPG level [(249.05±137.66) ng/L vs (226.67±170.12) ng/L], lowerserum sRANKL level [(0.11±0.08) pmol/L vs (0.12±0.02) pmol/L], and higher OPG/sRANKL ratio(202.31±219.24 vs 148.08±210.10), but these parameters were not significantly different betweenthese two groups. Multiple linear regression analysis showed that OPG/sRANKL ratio was anindependent factor of T score of lumbar vertebra. (3)Muhiple linear regression analysis revealed that vascular calcification score was an independent factor of T score of lumbar vertebra and hip.Conclusions Vascular calcification score is an independent factor of BMD of lumbar vertebra and hip in MHD patients. Serum OPG/sRANKL ratio may play an important role in the association between vascular calcification and BMD in MHD patients.

Arterial stiffness and associated factors in maintenance hemodialysis patients / 中华肾脏病杂志

Objective To study the arterial stiffness in maintenance hemodialysis (MHD)patients and to explore the associated factors. Methods Ninety MHD patients and 36 healthy controls were enrolled in the study.Automatic pulse wave velocity (PWV) measuring system was applied to examine carotid-femoral pulse wave velocity(CFPWV)and carotid-radial PWV(CRPWV)as the parameters reflecting central elastic large arterial and peripheral muscular medium-sized arterial elasticity respectively.Blood pressure and biochemical parameters were detected.Backward muhiple linear regression analysis was used to assess the influencing factors of arterial stiffness.Results CFPWV and CRPWV in MHD patients were greater than those of healthy controls [(13.22±3.23)m/s vs(10.67±2.11)m/s and(9.58±1.87)m/s vs(8.81±1.09)m/s,all P＜0.05].Backward multiple regression analysis demonstrated that age and pulse pressure were positively correlated with CFPWV,while dialysis duration,calcium phosphorus product,parathyroid hormone,low density lipoprotein and mean arterial blood pressure were signiticantly correlated with CRPWV.Volume reduction after single dialysis session could not improve arterial stiffness ofMIlD patients.Conclusions Arterial stiffness of large artery and peripheral muscular medium-sized artery increases in MHD patients.Age and pulse pressure are major determinants of large artery stiffness.Peripheral muscular medium-sized arterial stillness is more easily influenced by dialysis-associated factors.

Effects of low molecular weight heparin on vascular endothelial growth factor expression of early diabetic nephropathy / 北京大学学报(医学版)

Objective: To investigate the effects of low molecular weight heparin(LMWH) on vascular endothelial growth factor(VEGF) expression of early diabetic nephropathy. Methods: Ninety-five male SD rats were randomly divided into three groups: normal control rats, STZ-induced diabetic rats and diabetic rats treated with LMWH. The renal tissues were subjected to immunohistochemical staining after 1,2,4,6,and 8 weeks’ treatment respectively to quantify the VEGF expression. Results: Immunohistochemical staining demonstrated an increasing in VEGF positive cells in diabetic rats. It was found that there were significant differences in VEGF staining intensity between diabetic rats and normal control rats and between LMWH treated rats and untreated diabetic rats after two weeks treatment. Conclusion: The inhibition of VEGF expression may be one of the mechanisms of LMWH’s renal protective effects on early diabetic nephropathy.